[sane-devel] Bleedthrough (was brightness/contrast/gamma LUT ideas?)

[m. allan noah]

On Tue, 11 Jul 2006, Jim McQuillan wrote:

>>> i've found that documents printed on 20lb paper are getting some
>>> "bleed through". That is, the scan of the front is actually showing
>>> some of the stuff that is on the back of the page.
>>> I'm thinking that if I could reduce the brightness of the light, it
>>> may not bleed through so badly.
>> 
>> Maybe, but I think you will get better results by using a black
>> backing. It's a puzzle to me why so many scanners use white backing.
>> 
> Sorry, but I don't understand what you mean by 'black backing'. Could you 
> please explain?

background color, behind the page. some flatbeds have a black sheet you 
can put in the lid, your very expensive fujitsu adf has a servo operated 
shutter or mirror that moves in response to a scsi command. this is 
supported in the most recent cvs versions of the backend.

allan

-- 
"so don't tell us it can't be done, putting down what you don't know.
money isn't our god, integrity will free our souls" - Max Cavalera